Moptipy

We added the [signed permutations](https://thomasweise.github.io/moptipy/moptipy.spaces.html#module-moptipy.spaces.signed_permutations) space as well as [corresponding tests](https://thomasweise.github.io/moptipy/moptipy.tests.html#module-moptipy.tests.on_signed_permutations) as well as a [nullary](https://thomasweise.github.io/moptipy/moptipy.operators.signed_permutations.html#module-moptipy.operators.signed_permutations.op0_shuffle_and_flip) and a [unary](https://thomasweise.github.io/moptipy/moptipy.operators.signed_permutations.html#module-moptipy.operators.signed_permutations.op1_swap_2_or_flip) operator.

minor improvements and bug fixes

- better doctests for nputils
- more consistent behavior of some nputils functions
- caching of JSSP instances
- slightly better documentation
- added type annotations here and there

We added py.typed to allow typecheckers like mypy to check types when using moptipy.

pdfo in [version 1.3](https://pypi.org/project/pdfo/1.3/) uses `np.int`, which was deprecated and now [removed](https://github.com/numpy/numpy/pull/22607), from numpy [version 1.24.0](https://pypi.org/project/numpy/1.24.0/); i.e., deprecation of `np.int` has [expired](https://numpy.org/doc/1.24/release/1.24.0-notes.html#expired-deprecations).
This causes pdfo to throw an exception, as I detailed in their [issue 55](https://github.com/pdfo/pdfo/issues/55).
The pdfo developers will very soon fix this.
But for now, the newest versions of pdfo and numpy do not work together.
We implemented a temporary fix that simply lets our pdfo wrapper perform a random sample step and then quit if this version incompatibility is detected.
So right now, if you install our package, the [pdfo optimizer][(https://thomasweise.github.io/moptipy/moptipy.algorithms.so.vector.html#module-moptipy.algorithms.so.vector.pdfo) will not work.
But it will be fixed soon by the pdfo developers anyway - they already patched it in their [code base](https://github.com/pdfo/pdfo/commit/508369b372367d4549337c9cba62a5e46ae0e53d).

We also introduced a couple of minor fixes and improvements and stepped the dependency versions.

- BugFix in [Op1SwapTryN](https://thomasweise.github.io/moptipy/moptipy.operators.permutations.html#module-moptipy.operators.permutations.op1_swap_try_n) Operator: It swapped one element too many
- Better tests for detecting the above behavior

- Added max_step Parameter to PPA Implementation
- Version Stepping of Build Tools and Dependencies